The US State Department for the first time listed the Vatican as potentially vulnerable to money laundering, along with 67 other countries.
The department's annual International Narcotics Control Strategy report listed the Vatican as a "jurisdiction of concern" along with countries like Albania, the Czech Republic, Egypt, South Korea, Malaysia, Vietnam and Yemen.
It said the Holy See appears for the "first time" in the annual report.
Vatican City set up anti-money laundering programs for the first time in 2011 and it will take a year to start determining how effective they are, a State Department official told AFP on condition of anonymity.
It is "potentially vulnerable" to the problem as massive amounts of money flow into the Vatican from around the world, the official said.
"Jurisdictions of concern" are a notch below that of "jurisdictions of primary concern," which amount to a watchlist of "major money laundering countries," the report said.
The latter is a wide-ranging list of 66 countries that includes Afghanistan, Australia, Brazil, the Cayman Islands, China, Japan, Russia, the United Kingdom, the United States, Uruguay, and Zimbabwe.